Sharapova surrendered her world number one ranking after losing to Lisicki in the Wimbledon fourth round earlier this month,

But the French Open champion will have a chance to make amends by knocking out the German when they clash in the last 16 of the Games.

The 25-year-old, playing in her first Olympics, was pushed hard by home favourite Robson on Wimbledon's Centre Court, but she eventually subdued the 18-year-old, ranked 98th in the world, in one hour and 46 minutes.

"Laura played some really good tennis and I am just happy that I got through that one," said Sharapova, who felt Robson had thrived on the support of the British crowd.

"I was up in both of the sets but she came back at me so I am happy that I won in two."

"Of course it is always nice to play in front of a home crowd and that was certainly expected today. I think that she played really well."

Robson, who also lost to Sharapova at Wimbledon in 2011, added: "It's tough playing against someone like that because you have to go for so much on your serve, otherwise she's just going to start ripping returns.

"She definitely puts you under pressure. She won the French Open so she's obviously in great form.

"I had chances I didn't take so it's definitely disappointing, but I've still got the mixed doubles (with Andy Murray) to look forward to."